Yarn-carrier presenting means of tuft-fabric looms



April 3, 1945. w. BlxBY 2,372,758

YARN-CARRIER PRESENTI'NG MEANS OF TUFT-FABRIC 4LOOMS Filed May 21, 1940v 2 shuts-sheet 1 4350 aE-zv {pall/.7,3% Mmm fm.. /rrys Aprila, 1945. w. BlxBY 2,372,758

YARN-CARRIER PRESENTING MEANS OF TURF-FABRIC LOOMS 4 r-iied May 21, 1940 2 sheets-smet 2 INVENTOR Wm 75,? 51x sv #fins Patented Apr, 3, 1945 UNITED STATES PATENT OFFICE YARN-CARRIER PRESENTING MEANS OF TUFT-FABRIU LOOMS Walter Bixby, Boston, Mass., assignor to Shawmut Engineering Company, Dorchester, Mass., a corporation of Massachusetts Application May 21, 1940, Serial No. 336,379 5 claims. (lol. 13s- 7) My present invention relates to weaving mechchains and between the latter and the wheels or l sprockets about which they travel. Among the resulting beneiits are the production of a more even fabric, a substantial saving in the quantity of'tufting yarn expended in fabricating a given carpet or like tufted web, and various mechanical economies such as reduced requirements for renewal of parts.

In the drawings illustrating by way of example certain embodiments of the invention:

Fig. 1 is an elevational view of a wheel 0r sprocket and the associated chain of the carrier conveying means, with parts in vertical section taken substantially on the line I-l f Fig. 2;

Fig. 2 is a plan of a` short section of the chain. or conveyor means and of the releasable attaching device for connecting the adjacentend of a yarn carrier or tube frame to the chain;

Fig. 3 is a view of the mechanism of Fig. 1 .as seen from the right-hand of said figure, with the conveyor means in cross-section as if on the line 3--3 of Fig. 1, an end portion of one yarn carrier or tube frame supported on the chain being seen in elevation;

Fig. 4, partly diagrammatic and on a much re'- duced scale, shows a front portion of one loom side, including the overhead framework for the carrier conveying mechanism, including a number of the wheels or sprockets about which the carrier or tube frame supporting chains or conveyors travel;

Figs. 5 and 6 are respectivelya side and a front elevation of a wheel or sprocket in accordance with the invention; i

Fig. 7 is a side view of an outer portion of a sprocket such as that of Fig. 5 and a few links of the associated carrier chain, on a larger scale, with one of the sprocket tooth members at the near side of the sprocket omitted for clearness 45 the pattern requirements.

Fig. 7a is a section as if on the line laf-1a of Fig. 7; V

Fig. 8 illustrates another construction for the parts seen in Fig.l 7;

.3;1 Fig. 8a is a cross-section of a double link as upon the line 8a-8a of Fig. 8;

Fig. 9, on sheet 1, shows one of the paired link elements of Fig. 7 separately, in perspective; and Fig. 10 is a fragmentary perspective view of a il) ;cast sprocket and a carrier chain representative of the construction heretofore known and upon which the present invention improves.

Referring to the drawings in more detail, the

invention is illustrated in connection with the 5;:well-known Shawmut Engineering Company type of yarn carrier or tube frame such as disclosed, for example, in Hathaway patents, N os. 1,528,611, 1,621,406, and others. These each comprise a bar or frame proper IU, generally of tubular structure,

`see Fig. 3, of a length to support one or a number of tuft-yarn spools Il, depending on the width of the particular fabric. They range from threequarter frames (fabric 3A of a yd.) and a single spool, up to wide-work frames of sixteen-quarter 252;; (4-yd. fabric) and even twenty-four-quarter (6-yd. fabric) with three or more spools in line.

Each spool has wound on it a supply of tufting yarns as indicated at l2 in Fig. 3. 'Ihe individual 30 yarns or tufting units project through correbi*spending guides or yarn tubes l 3, a series of which extends substantially the length of the frame. The spool or spools for each tube frame are rotatably supported at their ends by brackets on the frame, as seen at I4'in Fig. 3. Thus as each 'frame is presented at the weaving position in the loom its series of yarn ends may be inserted between the warp threads-and the required length of yarn drawn off to form the tufting or pile.

40 Such length is cut off from the spool supply and e-""woven into the fell of the rug or like fabric.

A large number of 'these carriers or tube frames, frequently several hundred, is provided on the loom, arranged in a certain order to meet They are supported """on two or more parallel conveyors or chains, at least one adjacent each end of the frames, at the opposite sidesoi the loom. These chains are composed of pivotally connected alternate single and double links, one such chain being repre- 'sented by the dot and dash line in Fig. 4 and indicated as a whole by the numeral I5. In most instances the tube frames are detachably ass0 ciated with the chains, so that they may be bodand its attaching rivets shown in cross-section; I 1.115" removed individually, Carried 0r wiped down into tuft-yarn inserting position and then replaced on the chains.

The frame suspension means as here illustrated is of said detachable type. It comprises, as best seen in Fig. aan arm or blade i6 for reception between the pairs of double or straddle links of the conveyor chains and a cooperating moveable lock member or hook lat-ch il having a bill ila for engaging over the inner link of said pairs. Similar suspension means, sometimes termed ears, are provided at each end of the tube frames and in the case of the long multiple-spool frames may also be located at an intermediate point, for engaging a similarly positioned intermediate suspension chain.

Fig. 4 shows on a smaller scale a few of thev tube frames iii and their supporting means as seen from the right side of the loom. A portion of the right loom side is indicated at 211i with the associated framework for the frame conveyors, including the uprights :2i andthe topbeam 22. The chain i5 passes over upper guide wheels:

or sprockets 23 such asseen' atf the;upper;left in Fig. 4, and down around a: relatively; smali sprocket or pull-over: 2l!r at the operative. or transfer position. This); sprocket" usually is'- a driven element and generallyI reversing means is provided so that theeconveyor' chainsV mayfbef' moved in either direction,. for repeat pattern purposes. Beyondithe pull-over 'sprocket- 2liv thef chain is looped around a-series. ofgingtermedi'ate and lower guide wheels'or'sprockets'vandr 25,'

respectively.

iron sprocket S` as heretoforeeknown; .illustrating the integrally cast' doublei teeth. or. guides earsl between which the' alternatedA` singletlinksv Sliof the chains are received. As there'.- seen;V the weight of the chainis largely,supported b'yfbear ing engagement offithei ends off thezdnublevlinks DL withY the curved-or slantedendfwallsof .said- Referring again'toFig, 4, vit willbe noted that fer station close to the fell ofthe goods, where? space is limited, necessitates a relatively small diameter for the pull-over sprocket 24,: as shown in Fig. 4, and a correspondingly smallznumber of teeth, generally six.` Thelower guidesprockets 25v usually are somewhatlarger, commonlyhaving nine teeth, while the intermediate andV upper guideA sprockets 25, which. directly take. the :substantial weight ofthe conveyors-.and.frames,-,de.- sirably are still larger, usually with about seventeen teeth.

In the travel of the tube.frames-.withtheir supporting chains, and in the course of the intermittent stopping and starting for the transfer and replacement of the successive frames. there is a tendency for the frames to sway, rock and jerk relative to the chains. heretofore constructed, for example as typified in Fig. 10, have been such that the side edges of the tube frame hooks or latches il wear grooves in the engaged concave double link members as the frames swayand jerk back and forth in passing over, under` and partly around thesupporting and guiding sprocket wheels. The effect of this is to increase the swaying motion', until occasionally a frame becomes detached from a chain and drops free at'one or both ends.

The chains asy This usually results in a broken frame and serious damage to various loom parts.

Another contributing factor in the swaying and irregular movement of the frames heretofore has been the manner of engagement oi the single links of the chain in the slotted or U- shaped teeth of the sprockets. As commonly constructed only a relatively small surface area of the double-walled sprocket teeth is contacted either vby the intermediate portions of the single chain links received between them or by the ends of the adjacent double links; again see Fig. i0. Hence even a comparatively slight wear varies thisengagement and produces an improper tting of the chain on the sprocket, frequently causing it to snap in and out of position thereon, with resultant jarring and increased swaying of the tube frames.

The above defects have become accentuated in recent years by reason o the demand ior wider. one-piecev rugs. To satisfyk this; Wider looms have been-built, producingv fabrics twelve', fteen and even eighteen feet wide and requiring tube frames of correspondingly f increased length and weight. With such frames their swaying, flopping and likeobjectionable motionrelative to the chains is proportionately greater: and the wear is more rapid, bothbetween the tube frame ears and the chain and between the latter and thesprocket teeth. And .as the extent of Wear increases the objectionable-movement of the tube frames on their chains becomes.all the greater.

Thisswaying and jerking motionswiththe con-'h sequent vibrations. set upj in" the frames,A tends to.

pull theyarn ends backinto'.the'tufttubes; so thatan insufficient length isfdrawn inthez weaving' operation. Lowvspotsin the rug or fabric4 ly overcome these deficiencies,- through an improved construction forthe conveyor chains andv the sprocket wheels, with particular reference tov the cooperative relation' bothasI between the wheels and the `chains and as betweenthe latter and thev tube framef suspension means, vwhereby excessive-swaying and jerking ofthe frames is avoided and the likelihood of dislodging of the frames is correspondingly reduced, withV accompanying reduction in replacement of worn parts and in wastage of tufting yarn.

IniaccordanceV with the present invention the conveyor chains I5 as a whole comprise, as customary, single links 3G and pairs of double or straddle links 3 l, 3| alternately disposed and pivotally connected as by means of the-transverse pivot members or rivets 32; see Figs. l to 3, '7 and 9. Each link has rivet holesdisposed concentrically of itsv rounded endformations substantially as at 35a, 3Ia in'Fig. 9.' These are-solocated that the adjacent ends of two successive serted laterally between two links 3i of a'pair and'with' the latches H engaging over tlieinner straddle link of the particular pair; see especially Figs. 1, 2 and 7.

The rivet elements 32, as seen at the left in Fig. 2, have an intermediate portion 33 of somewhat larger diameter than their opposite end portions 34, 34. The rivet apertures of the double links 3| and of the single links 30 are correspondingly proportioned to t respectively the reduced end portions 34 and the intermediate larger or bearing portion 33 of the rivets 32. Said larger intermediate portion 33 of the various rivets or pins terminates in opposed annular shoulder formations 33a, 33a. In the assembled chain the double or straddle links 3| abut or engage laterally against said shoulders 33a as stops, rather than merely against the adjacent side faces of the single links 30.

The double links 3| have a fairly tight iit on the reduced end portions 34 of the rivets and when the latter are headed over substantially as represented in Fig. 2, the double links are securely fastened in position on and relative to their rivets, so that ordinarily they have little or no turning movement upon them. But the intermediate rivet portions 33 and the apertures therefor in the single links 30 are proportioned to allow these single links to turn freely on said intermediate rivet portions 33 as bearings.

In further accordance with the invention the rivet elements or pins 32, formed of an appropriate metal stock such` for example as SAE 2315 steel, have their intermediate or bearing portions 33, including the lateral faces of the shoulder formations 33a, carbonized and hardened o1' otherwise treated to give them a substantial wearresistant character. The rivet end portions, receiving little or no wearing action, are left of a relatively soft character, to facilitate heading them over in making up the chains. Similarly, the single links 30, which as will be explained are constructed and arranged relative to the sprocket wheels to take directly a major portion of the load of the chains and frames, desirably are formed of a high-grade stock such for example as SAE 3140 specially heat-treated desirably throughout and particularly at their end bearing apertures and at the faces of their intermediate portions.' The particular shape of these single links and their cooperative relation to the sprocket wheels will be referred to in connection with the latter.

Referring now more particularly to the double links, these have generally heretofore been made concave at both top and bottom at their portions between the rivets, as represented in Fig. 10. As a result the substantially flat underface' of the bill Ila of the moveable element or latch of a tube frame ear, for engaging over the top face of the inner link of the pairs, has contacted the latter only with its opposite side edges, causing transverse grooves to Abe worn'in the top face of the link.

To overcome this, and noting particularly Fig.

9, I have made the double links 3| with straight l edges 35 along both the top and bottom of their intermediate outer side faces, and with planar top and bottom faces 35, 31 inclining inwardly upon a bevel from said straight outer edge portions 35. Thus, as best seen in cross-section in Fig. 3, the latch-receiving inner links of the pairs are made to conform in shape to that of the under face of the latch bills lla, providing between these two parts broad and plane engaging surfaces ofsubstantial extent both lengthwise and transversely of the chains. i

Desirably these double links 3| are symmetrically shaped at both their top and bottom half portions, with their beveled top and bottom faces 36, 3l oppositely disposed, that is, inclining inwardly toward each other. These links accordingly are completely reversible and may be installed in the chain either as the inner or the cuter member of the link pairs, with either edge uppermost. In other words, they are reversible both end for end and topfor bottom. Further, said inclined planar intermediate portions of the double links are so shaped and proportioned with respect to the substantially plane and similarly inclined intermediate projecting portions of the tube frame arms I6 that the latter and the adjacent face 31 of the ear-receiving link also have flatwise contact over a substantial area, again both lengthwise of and in the direction across the chain. As clearly seen in Fig. 3 the frame-supporting link of the various pairs 3| is in effect clamped planarly at both its top and bottom faces 36, 31 between the particular latch bill |'|a and said intermediate portion of the corresponding arm |6, with a broad and extensive planar surface engagement between the contacting parts, avoiding any fulcrum-like formation between them and affording them a rm seat one upon the other. Hence the capacity of the frames to rook or swing upon the chains in the direction lengthwise of the latter is materially reduced. This i5 due primarily to the described straight-edged formation for the double links 3| and their extensive plane top and bottom faces disposed to conform to and coopcrate with the enclosing portions of the tube frame suspension means Il, I6 respectively.

It will be noted that in the example as illustrated in Figs. l to 3, '7. '7a and 9, as well as that of Fig. 8, the shape of each double or straddle link 3| as viewed in cross-section taken at a point between the rivet apertures, see particularly Fig. 3, is non-rectangular. Preferably it is quadrilateral or substantially so, with at least two sides (the vertical sides in Fig. 3) parallel or nearly so and at least one (that at the top 36) of the other two sides (actually both in Fig.

3) oblique o-r non-perpendicular to the parallel sides. While in the illustration this cross-sectional .shape of the double links 3| is trapezoidal, with the two non-parallel sides substantially symmetrical, that is. of about equal length and equi-angular butA of opposite inclination, such trapezoidal shape need not besymmetrical, and other non-rectangular generally quadrilateral shapes may be employed, including trapezia, although usually of the substantially two-parallel- .sided form, such other shapes including the nonrectangular parallelograms classed as rhomboids and rhombs.

In any case that face 3S of the double link which is at the top as viewed in Fig. 3 is made plane and desirably is beveled or inclined to conform -to the under face of the latch bill Ila, whereas the opposite face 3l, that :at the bottom in Fig. 3, while also plane and preferably conforming to the adjacent surface of `the suspension arm I6, may variously be upwardly and inwardly inclined, at a greater or less angle, or otherwise disposed, either with an opposite inclination or perpendicularly to the substantially vertical or other` opposed pairof sides', dependl ing chiefly on the formation of such arm I6.

Turning now to the structure of the single links 30 and of the sprocket wheels with which they cooperate and referring rst-to the embodiment as in- Figs.v 1A to 7a, said single links have their' mainxor intermediate portions, between the rivety The herein narrower or top and bottom faces 30a, Stb, and particularly those at the bottom, also are fiat, that is, horizontal or substantially perpendicular to the side faces. In cross-section as seen in Fig. 7a these single links accordingly are rectangular or approximately so; In width, that is, in the vertical direction as viewed in Figs. 1 and 7a, these single links desirably correspond approximately to the greatest Width of the bevel-faced double links 3l. Thus they are somewhat wider than the rounded end portions of 'the double links, since the diameter of said double link ends, as clearly seen in Figs. 1 and?, is lessthan the greatest width of those links, by about the difference in widths f their two parallel side faces. In other words the inclined top andbottom portions 35, 31 of the double links SI-project laterally (vertically in Fig.` 1 position) beyond their rounded ends, as learly seen at the left in Fig. 9, while the sing e links 30 are each of uniform width (vertically of Fig. 1) equal to the maximum double-link width. This gives a measure of protection to the rounded ends of the double links, which latter accordingly may be of a softer and less expensive material thanv that of the single links, said latter'beingV preferably of a high-grade steel such asthe SAE 3140- steel previously mentioned, and being heat treated'or otherwise specially finished for Wear-- resistance.4

Heretofore the wheels or sprockets about which the chains pass have been made of cast iron,

with'the teeth and the other parts, including thel hubsvand the intermediate or disk parts of the sprocket all formed in the one casting. In said prior sprocket the teethv retain their contour substantially as cast, their longitudinal recessed portions, between the spaced walls of the double tooth-members, being machined or cored slightly Wider, after coming from the mold, to receive the single links of the chain.

Inaccordance with the present invention the' guiding tooth members of the sprocket wheels are'separatelyformed and replaceably mounted on the main body or disk of the sprocket, the hub or bearing portion of the latter also preferably being separately constructed and assembled with the intermediate wheel portion. It will be understood that said intermediate portionmay be a disk in the usual sense, that is, an approximately circular or annular plate substantially uninterrupted in the circumferential direction, or it may be otherwise formed, for example with spaced openings in the manner of a spider or rim-and-spoke,formation. The terms diskj Wheel body, radially intermediate portion and the like accordingly are intended to include such various constructions, whether circumferentially continuous and plate-like, or otherwise.

In the embodiment here illustrated by Way of example, referring now moreA particularly to Figs. 1 and 5 to 7a, a representative individual Wheel or sprocket is indicated as a whole by the numeral 4Q.' The general structure and the process of manufacture and assembly are the same for any of the sprockets 23, 24, or'26 regardlessxof` their particular size and the number of their-teeth. Said typical sprocket element .40'

comprises`V a separate hub 4| havinga radial flange 4Ia secured as by bolts Hb centrally-of a steel.l disk, plateror intermediate wheel portion 42." Such diskv hasa double series of radially projecting.peripheralvguides or tooth members 4'3 equally: distributed about and secured to its outerl edge or rim.

The sprocket hub 4l may be of any desired material. Where low cost'is important it is of cast iron, its radial flange Ma, see Fig. 6, being cast invone piece with the bearing portion or hub proper and apertured to receive the disk-attaching bolts seen in Figs. 5 and 6. The hub may be variously otherwise formed or attached, as by welding a steel hub.

Asherein represented the radially intermediate or main wheel element or disk 42' comprises a flat orv substantially fiat plate centrally apertured for'reception on the hub M. A circumferential series of holes to receive the hub bolts kHbl is punched, drilled or otherwise formed conform to links of the chain, as by means of' appropriately arranged dies or punch elements,

including in said operation the formation of the link-seatsll` and the recesses 45 to be described. thereby materially simplifying and expediting the manufacturing process.

Said outer` series of holes Q2u are for reception of rivets used in attaching the tooth members 43. to be described'in further detail. While in some instances a single rivet for each tooth may be found adequate,A provision preferably is made for a plurality of rivets. at least two for each double-walled tooth element. disposed' in equally spaced pairs, substantially as seen in Fig. 5; 'The particular sprocket ill there shown is one of the larger ones such as in the upper series 23 orl the intermediate series 25 of Fig. 4, there being-in thisv instance seventeen of the doublewalled toothv elements. 43 and hence seventeen pairs of rivets and rivet holes 42a around the disk rim. But the construction and method of making-the several sprockets may be the same irrespective of the sprocket diameter and the number of 'its teeth. In fact it is one of the main advantages of the present invention that the wheel and the chain construction is such that the individual link-engaging portions of all sprockets, whatever the sprocket diameter, are all uniformly of the same size and shape. As a result there is substantially identical cooperative engagement between the given chain and each and 'every'wheel or sprocket about which it trav- Y els, irrespective of any differences in sprocket v diameter andv in number of teeth, whether there angles and all equally spaced. The length of each seat 44 substantially corresponds to that i of the single links between their rivet centers. Thus as each single link 30 of a chain reaches a sprocket its plane and herein flat under or inner face 30h engages flatwise against one of said seats 44 in accurate guided relation and with direct surface contact of substantial area, equivalent to the entire under face of the link.

Between these single-link seats 44 the rim of the disk 42 is recessed or cut-away along an arcuate or other contour, as indicated at 45 in Figs. 1 and 7, to aord ample clearance for the suspension elements such as the arms or blades I6 and latches Il of the tube frames.

The separately formed sprocket tooth members 43 are assembled in pairs, one member of each pair disposed flatwise against each side face of the disk 42, opposite each of the link seats 44. Thus in the illustrated example there are two series of tooth members, one at eachside of the disk and transversely aligned so as to form in effect a peripheral series of double-walled tooth units 43 for `lateral guiding and positioning redisposed, thus reducing wear and extending the life of the tube frame conveying mechanism as a whole. Moreover, due to the seating engagement of substantially the entire underfaces 30h of the single links directly with the like-formed and accurately tting seats 44 of the sprocket over the large area of direct surface contact such as seen in Figs. 7 and 7a, there is a uniformly accurate and positive guided relation between the chain and each of the sprockets, whatever the diameter of the latter. Thus the objectionable swaying and jerking of the tube 'frames is materially reduced and largely eliminated, despite the numerception of the single or connecting links between them; see particularly Figs. 2 and 7a. While this individual construction for the two side members or sections of these double-walled tooth units facilitates and reduces the cost of large-scale manufacture they may be integrally formed with slotted bases adapted to straddle the disk rim, in which case the link-seating surfaces corresponding-to the seats ,44 of the disk'are on the tooth units, at the bottom of the space between thetwo projecting wall portions.

The separately-formed tooth members 43, whether of the two-piece paired construction or otherwise, preferably are fashioned from a hard, tough stock of highly wear resistant character. In practice I have employed for the purpose a special alloy steel, more specifically SAE 2.330 steel, and I subject the tooth members 43 to hardening heat treatment further to increase their durability.` The attaching or base portion 43a of each tooth member has one or more rivet holes, preferably at least two, disposed to align with the holes 42a about the rim of the disk. The connecting rivets 46 are headed over'to hold the toothmembers securely on the disk and in addition, or as an alternative for the attachment by riveting, interengaging portions of the'teeth and disk may be welded together. These separately fashioned tooth elements 43 may subsequently be readily removed and replaced if necessary. The radially projecting or upstanding double wall portions of the teeth 43 have a contour and angular extent, circumferentially of the sprocket 40, to conform them to the rounded end portions vof the adjacent pairs of the double or straddle links 3| and to the tooth-receiving spaces longitudinally intermediate said end portions, transversely opposite the single connecting links 30.

By means of the described tooth and sprocket construction the main load of the chains and frames is taken directly by the edge face of the disk portion of the wheel, at the spaced positions where the various single links fit and rest with their contacting faces 3Ub against the seatngvformations 44 of thedisk. Substantially all the weight is thus taken from the projecting tooth members themselves, where it has heretofore been ous different positions which they must assume, as seen in Fig; 4, in the course of their mutually parallel travel with the advancing or retreating carrier chains.

The advantage of the large area surface interengagement between the single chainI links 30 and the seat formations 44 on the sprocket disks proper will be further evident when it is considered that as a chain becomes broken in, and subsequently throughout its period of use, `there inevitably is some degree of longitudinal stretching of the chain as a whole, although this has been reduced to a minimum by the disclosed link and rivet or pivot pin construction. Heretofore the single links of the chain have had but limited and uncertain engagement, frequently only along a lower corner portion, in the recessed portions of the cast-iron sprocket teeth, such as shown in Fig. 10. As the chain elongates, this engagement, generally of but substantially a linear character lengthwise the cast teeth inner faces, tends to shift in toward the center of the sprocket. This in turn brings the rounded ends of the douvble link units, which take the main load, farther down onto the end walls of the sprocket teeth, increasing the wear between said parts.

These factors all contribute to a rapid wearing of the chain as a whole and also of the cast-iron sprocket teeth. Looseness and play between the parts results at some points, while an irregular binding action may occur at others, causing objectionable jerking and snapping movements of the chains in their engagement with and release from the sprockets. These movements are directly. conveyed to the supported tube frames so that their swaying, jouncing and vibratory movements are dangerously increased, with the highly objectionable results already pointed out.

But since in accordance with the present invention the single links 36 are directly supported by interfitting surface engagement of their faces 30h upon the sprocket disk itself, at its seat formations 44, throughout substantially the entire length of said links, elongation of the chain is immaterial. And where the rounded end por tions of the double link `members 3i have a less diameter or width than the portions of the single links which they overlap, as represented for veX- ample in Fig. 7, there is little opportunity for wearing engagement between the double link `ends vand the end walls of the sprocket tooth members 43, 43a. The interaction and cooperative relation of the sprockets and chains ac-4 fact thatthe tubesframeconveyor chains have a highly intermittent movement, now travelling in one direction,'then 4halting for removal and replacement ofthe presented tube frame, and

then resuming travel, sometimes in the same direction andat other times reversely, according .to the requirements of the particular rug or other fabric pattern.

Figs. `8 and 8a illustrate a somewhat modified sprocket and chain structure embodying the in-y vention. yIn these figures corresponding parts bear the same reference numerals as in the previous views, withthe addition of a prime mark.'

In this instance the chain-again consists of pairs of double or straddle links 3l alternating with the single'or connector links 30', these alternating single links and spaced link pairs being pivotally connected by the rivets 32', preferably of the material and construction, including a hardened intermediate or bearing portion ofl larger diameter than the end portions, as in Figs. 1 to '7a.

The sprocket :wheel or element 40 desirably is formed by the same process-and has a generally similarstructure asy already described. In,-

this instance-the chain as'a whole is of a somewhat lighter character, being especially appropriate for use with the intermediate and shorter tube frames. The single links fi are shown as being somewhat longer than the double links-iff 3',alsoras-appropriate in such instances. The separately formed tooth Vmembers 43 of the sprocket disk '42 have a length circumferentially-of thedisk corresponding to that of said single links 30', while the recesses 45 at the.;

radius yof the disk d'2 itself. With respect to this concave contour the single links 35i more resemble the-corresponding chain elements heretofore employed, 'but as-fnoted the radius of vcurvature of their concave portions desirably is made less than the vradius ofthe-sprocket'or'wheel as@ a whole.

In order to provide for these concave links -Sl a similar positive-guided and direct seating cooperative relation to `the sprocket, the seat formations d' at the'rim of the latter, opposite..

said single links, are curved convexly lin conformity with thecontour of the single links, as clearly seen in Fig. 8, and as contrasted with the rectilineai` and plane-faced formation for the contacting portions Elib of the single links.;

3i] and the seats lili-on the sprocket disks in the preceding figures. But as in said'early figures a direct surface to surface supporting contact of large total area is obtained by the described concavo-convexmatching contour of the single.

links 3U and the link seats fifi. The doublewalled sprocket tooth elements it', similarly as in the earlier views, 4are fashioned separately from the sprocket'disk 12' and vattached as by the rivets 45', with or without the use of weld.

ing.

Similarly as in the previous example, the individual members of the `double link pairs 3|', as best seen in cross-section in Fig. 8a, are formed to have large-area plane seating enlasf/2,758

gagementwith the tube frame suspension means, in cooperative relation both at the plane under face ofthe latch bills for reception across the top or outer faces 36 of these links and with the underlying plane surface of the arm or blade of the suspension device, in the general manner as already described with particular reference to Fig. 3. Said top or outer edge faces 36' accordingly are made planar and are inclined transversely to conform with the like inclination of the latch bills. The inner or bottom edge faces 3l also-are planar .and herein are inclined at approximately the same angle but oppositely to the outer faces 36', for conforming engagement in firm `seated relation with vthe similarly inclined planar upper surface of a tube frame arm or blade, such as represented at l5 in Fig. 3. As in the earliergures, the planar under faces 3l of the Fig. 8 linksI-Ilmay have various different inclination or may be perpendicular to the side walls, following the various cross-sectional shapes as previously described herein, depending on the positioning of the top surface of the suspension arms with which they are to cooperate.

Thus the individual double link members 3 l are in general substantially the same as in the earlier figures, but as illustrated in said Figs. 8 and 8a their overall width, that is, in the direction radially of the sprocket wheels or vertically as viewed in a position such as that of Fig. 3, does not appreciably or at all exceed the diametral width of their rounded ends. As clearly seen in Fig. 8, and as indicated by the non-hatched triangular parts at the top and bottom of Fig. 8a, the side edges of these links 3l', at their wider side faces, showa straight line throughout the length of the link between the points perpendicularly opposite the centers of the rivet holes. the narrower or'edge faces 36 and 3? being beveled or inclined from said edges to form the planar seats for'the latch bills and arms respectively of the tube framev suspension means.

lFrom a manufacturing standpoint said construction is somewhat less desirable than the laterally projecting formation of the previous figures, notingparticularly Fig. 7, because the Fig. 8 form involves machining operations at said top and bottom faces`3ii and 3l whereas in the formof Fig. '7 the stockfrom which the linksaf are formed may initially'be rolled and supplied in continuous lengths of uniform cross-sectional shape such as that seen in Fig. 3, the individual links being .stamped out and their reduced rounded ends simultaneously formed in a single stamping or die-press operation.

From the foregoing description taken in connection with the drawings, it will be apparent that my present invention comprises the processesand methods of manufacture for the tube frame conveyor wheels or sprockets of Axminster and like looms and for the cooperatively associated conveyor chains, as well as the novelly cooperative structure of such conveyor mechanism, including the sprocket and the chain elements, both individually and in new functional relation and combination with lthe suspension `devices vof theyarn carriers or tube frames of vsuch looms.

vor described, and I set forth itsscope in my following claims:

I claim:

l. A link for a tube frame conveying chain for an Axminster loom of the type employing tubeframes equipped with supporting means including latches with bills having plane underfaces and including associated arms having angular portions vertically opposite the latch bills in the normal position of the latter, said link having rounded end portions apertured for pivotal connection to other links and having a substantially uniform trapezoidal cross-section throughout between said end portions, the two non-parallel sides of said section lying in opposed longitudinally extensive plane surfaces, one of the latter formed to engage planarly the under face of such tube frame supporting latch bill and the other similarly to engage simultaneously the opposite intermediate angular portion of such tube frame arm.

2. A tube frame carrier chain comprising a series of single links alternating with pairs of straddle links, said single links adapted for pivotal connection at each end to adjacent pairs of the straddle links, with the ends of the single links disposed between and overlapped by the ends of the straddle links, all said links having at each of their ends transverse apertures for re- .ception of rivet pin connectors, the apertures in at least the single links being circular and of larger area than those of the straddle links, and rivet connector and bearing pinssaid pins each comprising an intermediate portion of cylindrical form for reception in the apertures of the single links to provide pivot bearings therefor, and opposite end portions of reduced cross-sec tional area as compared with that of the intermediatevportion and shaped for close fitting reception in the straddle link apertureawthe inner faces of the straddle links adapted td'labut the shoulder formations at the ends of the intermediate pin portions alorded by the relatively larger cross-sectional area thereof, said end portions of the pins having alength to project outwardly beyond the paired straddle links and there to be headed over firmly to secure the latter upon the pins, said rivet pins being formed of steel and having at least the bearing surface of their intermediate portions of relatively hard wear-resistant characters as compared with the pin end portions.

3. A tube frame carrier chain according to claim 2 wherein the single links are formed of a high-grade steel and are heat-treated to highly wear-resistant hardness at least at their end portions, including the pin-receiving pivotal bearing walls of their apertures.

4. In a tuft fabric loom of the type employing tube-frames having suspension means including a latch having an angular bill with an extensive plane under face; a tubeframe conveying chain comprising a series of alternated single links and pairs of dou-ble links, each of said links having apertured rounded end portions for pivotal interconnection, the intermediate portions of the double links between their end portions having straight side edges and being of substantially uniform quadrilateral cross-section throughout, with two opposite sides parallel and with one of the other two sides non-perpendicular to the parallel sides and disposed at such angle relative to vthem as to provide for said links a longitudinal edge face adapted for intimate intertting parallel planar supporting engagement with such planar under face of a tube-frame latch bill.

5. In a tuft fabric loom of the type employing tube-frames having suspension means including a latch having an angular bill with an extensive plane underface and having a cooperative arm with a upright end and an intermediate angular portion vertically opposite such latch bill; a tube frame conveying chain comprising a series of alternated single links and pairs of double links` each of said links having apertured rounded end portions for pivotal interconnection, the intermediate portions of the double links between their end portions having straight side edges and being of substantially uniform trapezoidal crosssection throughout, with two opposite sides parallel andwith the other two sides disposed at such angle relative to them as to provide for the side links a longitudinal edge face adapted for extensive face-to-face planar engagement with such planar underface of a tube-frame latch bill and further t0 provide for said links an opposite longitudinal edge face for similar extensive planar engagement simultaneously with such intermediate angular portion of a tube-frame arm.

WALTER BIXBY. 

